<!DOCTYPE html>
<html>
    <head>
        <meta charset="UTF-8">
        <title>WebSocket</title>
    </head>
    <body>
        <input id="url" type="text" size="60" value="ws://localhost:8001/web_socket/order_notification/M666666" />
        <button onclick="openWebSocket()">打开WebSocket连接</button>


        <button onclick="closeWebSocket()">关闭WebSocket连接</button>
    
        <div id="message"></div>
    </body>
    <script type="text/javascript">
     　 var websocket = null;
 　　function openWebSocket() {
      var url = document.getElementById('url').value.trim();
      //判断当前浏览器是否支持WebSocket
            if ('WebSocket' in window) {
            websocket = new WebSocket(url);
      } else {
            alert('当前浏览器 Not support websocket')
      }
      //连接发生错误的回调方法
            websocket.onerror = function() {
            setMessageInnerHTML("WebSocket连接发生错误");
      };
      //连接成功建立的回调方法
            websocket.onopen = function() {
            setMessageInnerHTML("WebSocket连接成功");
      }
      //接收到消息的回调方法
            websocket.onmessage = function(event) {
            setMessageInnerHTML(event.data);
      }
      //连接关闭的回调方法
            websocket.onclose = function() {
            setMessageInnerHTML("WebSocket连接关闭");
      }
    }
    //监听窗口关闭事件，当窗口关闭时，主动去关闭websocket连接，防止连接还没断开就关闭窗口，server端会抛异常。
        window.onbeforeunload = function() {
        closeWebSocket();
    }
    //将消息显示在网页上
        function setMessageInnerHTML(innerHTML) {
        document.getElementById('message').innerHTML += innerHTML + '<br/>';
    }
    //关闭WebSocket连接
        function closeWebSocket() {
        websocket.close();
    }
  </script>
</html>